Icom IC-7000 Marine Radio User Manual


 
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PACKET OPERATION
Packet operation
q
w
e
y
t
r
PIN #/NAME DESCRIPTION
q
DATA IN
Communication data input.
w
GND
Ground for DATA IN, DATA OUT and AF OUT.
Transmits when grounded.
e
PTTP
When grounded, microphone input (pin 6) of [MIC]
connector will be disconnected.
r
DATA OUT
Outputs 9600 bps receive data.
t
AF OUT
Outputs 1200 bps receive data.
y
SQL
Squelch output.
Goes to ground when squelch opens.
Rear panel view
DAdjusting the data speed
qSelect
M
-
3
.
wPush [F-4
9600
] to select the 9600 mode ON and
OFF.
“”appears when the 9600 mode is activated.
[MENU/GRP] [F-4]
DAdjusting the transmit signal output from the TNC
When setting data transmission speed to 9600 bps,
the data signal coming from the TNC is applied ex-
clusively to the internal limiter circuitry to automati-
cally maintain bandwidth.
NEVER apply data levels from the TNC of over 0.6
Vp-p, otherwise the transceiver will not be able to
maintain the band width and may possibly interfere
with other stations.
NOTE: Read the instructions supplied with your
TNC carefully before attempting packet operation
with the IC-7000.
1.When using a level meter or synchroscope, adjust
the TX audio level (DATA IN level) from the TNC as
follows.
0.4 Vp-p (0.2 Vrms): recommended level
0.2–0.5 Vp-p (0.1–0.25 Vrms): acceptable level
2.When not using a measuring device.
Connect the IC-7000 to a TNC.
Enter a test mode (“CAL”, etc.) on the TNC, then
transmit some test data.
When the transceiver fails to transmit test data or
transmits sporadically ([TX] indicator doesn’t light
red or blinks):
- Decrease the TNC output level until [TX] indica-
tor lights red continuously.
When transmission is not successful even though
[TX] indicator lights red continuously:
- Increase the TNC output level.
DData socket
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